Coarticulatory effects of stop voicing on F0 from voicing onset to vowel target

Abstract

Fundamental frequency perturbations due to stop voicing were measured using a computer waveform editing program for the first five pitch periods and vowel target. Five adult males recorded five repetitions each of voiceless aspirated /ph, th, kh/, voiceless unaspirated /sp, st, sk/ and voiced /b, d, g/ stops in combination with the vowels /i, e, u, o, a/. Voice onset time (VOT) was determined for each utterance. Mean differences in VOT between voiceless unaspirated and voiced stops collapsed across vowels were only 3, 6, and 4 Hz for bilabial, alveolar, and velar places of articulation, respectively, whereas comparable differences between voiceless unaspirated and voiceless aspirated stops were 42, 56, and 47 Hz. In general, F0 fell from the first pitch period to the second pitch period for all voicing conditions. The average magnitude of this fall was greatest for voiceless unaspirated stops and least for voiced stops. Slight changes in F0 occurred from the second pitch period to the vowel target. Moreover, the average absolute differences in F0 between voiceless unaspirated and voiceless aspirated stops for the second pitch period to vowel target never exceeded 3 Hz compared to at least a 9‐Hz differential between voiceless unaspirated and voiced stops. The results indicate the importance of F0 change at voicing onset as a property that distinguishes not only voiceless aspirated from voiced stops but also voiceless unaspirated from voiced stops. [Work supported in part by NINCDS.]